Floorcoverings stabilized with pressed-in fibrous layers

ABSTRACT

Reinforcing fibers insensitive to thermal and hydroscopic expansion or contraction are inserted into the backside of a textile fabric using embossing with a fine and deep pattern of projections or cupped needles and held in place with adhesive. The process allows the stabilization of layers having a high sensitivity to variations in temperature or humidity in constructions when the stabilizing fibers cannot be included in the original fabric-forming process, as in the case of a tufted fabric using fiberglass fibers for stabilization.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application claims priority to U.S. Provisional Patent Application No. 62/730,310, filed Sep. 12, 2018, the entire contents of which are incorporated herein by reference.

TECHNICAL FIELD

The present invention is directed to stabilization of floorcoverings containing at least one fibrous layer through insertion of highly stable fibrous elements insensitive to temperature and humidity variations into the back face of the fibrous floorcovering in a post-formation step.

BACKGROUND

Floorcoverings are required to lay flat on a floor and stay flat, without substantially expanding, contracting or warping out-of-plane as mechanical stressing caused by traffic or changes in thermal and hygroscopic conditions affect their dimensions and their flatness. Previous attempts at avoiding these problems added stabilizing layers including highly stable woven or nonwoven layers and other forms of fiberglass and similar materials unaffected by temperature and humidity to floorcoverings. For some fibrous flooring structures, these stabilizing layers are added to the floor coverings above or below fibrous layers to which the reinforcing elements could not be added during the original fabric formation process. For example, in tufted structures and needle-punched structures, layers such as glass fiber layers can interfere with the tufting or needling process. This interference can result in problems such as the projection of glass fibers onto the surface of the floorcovering, nonuniformities in the product, and damage to needles.

However, attaching the stabilizing layers above or below the fibrous layers leaves substantial layers of the fabric free to expand and contract. As a result, these fibrous layers remain susceptible to substantial dimensional changes during use, and the composite floorcovering itself remains susceptible to warping, or to gaping between seams when installed on the floor. Therefore, a need exists for methods that stabilize fibrous floor coverings against deformations caused by changes in temperature and moisture content using dimensionally stable materials.

SUMMARY

Exemplary embodiments are directed to stabilized fibrous floorcoverings containing dimensionally stable fibers embedded in a textile fabric. In one embodiment, the dimensionally stable fibers are brittle fibers, e.g., fiberglass. The dimensionally stable fibers are introduced into the back face and lower layers of the floorcovering by pressing a layer of dimensionally-stable fibers into and through the back face and lower layers of the floorcovering. The inserted stabilizing layer can be in the form of a staple fiber web, a warp of filaments or yarns, or a woven or nonwoven fabric. Low-melt adhesive binder may be present in the original fabric, may be added prior to the embedding process, or may be added after the embedding process and activated after the insertion of the stabilizing fibers. Alternatively, melted or dissolved binder is added to the back face receiving the stabilizing fibers after the insertion and activated to secure all fibers together. The dimensionally stable fiber layers are inserted or embedded by pressing with plates or calender rolls equipped with three-dimensional patterns of surface projections. For example, the calender rolls and plates have patterns of relatively deep face projections. Alternatively, the plates or rolls are equipped with an arrangement of shallow cupped needles, or very shallow heavy-gage barbed needles. Insertion and embedding may require several passes or a large number of shallow strokes. These patterns embed the dimensionally stable fibers into the textile fabric from the back face and stabilize the previously unstable back layers adjacent the back face. This process is useful for fabrics that could not tolerate the introduction of dimensionally stable and brittle fibers during the initial process of forming the textile fabric and floor covering. Dimensionally stable fibers such as glass or aramid fibers tend to be brittle and abrasive and tend to damage the finer stitching or needle-punching or tufting needles, to interfere with the initial fabric formation, and to appear on the surface of the fabric or floorcovering.

Exemplary embodiments can be used with textile fabrics such as needle-punched textile fabrics, tufted textile fabrics and woven textile fabrics. For example, dimensionally stable fibers are forced through the face or back of a needle-punched textile fabric and along a portion of the thickness of the fabric. Alternatively, an arrangement of cupping needles on a plate or roll are used to embed the dimensionally stable fibers into a needle-punched textile fabric to a relatively shallow depth. The layer of dimensionally stable fibers can be in a loose web form or in an entangled, bonded, inter-woven or inter-knit form. Insertion of the dimensionally stable fibers may also simultaneously break, disentangle, and reorient the stabilizing fibers and intermesh them with the fibers within the fabric being stabilized either randomly or systematically to achieve multi-directional planar stabilization. In another example, a layer of dimensionally stable glass, aramid or similar fibers are embedded not only around but also into the back-laps of a tufted textile fabric, and between the filaments or fibers forming the back-lap yarns, either before or after the application of an adhesive precoat to the back-laps. This is followed by a second adhesive coat to stabilize fibers projecting from the back surface.

Exemplary embodiments are directed to a textile fabric having a top face, a back face spaced from the top face by a thickness and a plurality of textile fibers located within the textile fabric between the top face and the back face. In one embodiment, the textile fabric is a needle-punched fabric.

A stabilized layer extends into the textile fabric and partially along the thickness from the back face. The stabilized layer includes a plurality of dimensionally stable fibers intermeshed with a portion of the textile fibers and an inter-bonding adhesive. In one embodiment, the dimensionally stable fibers are glass or aramid fibers. In one embodiment, the dimensionally stable fibers have a low coefficient of thermal expansion. In one embodiment, the inter-bonding adhesive is a low-melt adhesive. Each dimensionally stable fiber maintains dimensional stability upon exposure to changes in moisture, changes in temperate or changes in moisture and temperature. In one embodiment, the inter-bonding adhesive is a low-melt adhesive having an adhesive melting point lower than a textile fiber melting point. In one embodiment, the inter-bonding adhesive is a liquid adhesive introduced after the dimensionally stable fibers have been inserted into the back face of the fabric and cured. In one embodiment, the textile fabric includes an additional layer attached to the bottom face and in contact with the stabilized layer.

In one embodiment, the textile fabric is a tufted fabric having a primary backing between the top face and the back face. The textile fibers are yarns tufted into the primary backing at a plurality of yarn insertion points to define face loops extending from a first side of the primary backing to the top face and back-laps extending from a second side of the primary backing opposite the first side to the back face. The stabilized layer extends from the back face through the back-laps to the primary backing, and the dimensionally stable fibers are intermeshed with the back-laps and at least a portion of individual fibers within the back-laps. In one embodiment, the dimensionally stable fibers are intermeshed with the backlaps in accordance with a pattern of insertion points having an insertion point frequency across the back face that exceeds a yarn insertion point frequency across the primary backing. In one embodiment, the inter-bonding adhesive extends from the back face through the back-laps and at least partially through the primary backing from the second side.

Exemplary embodiments are also directed to a method for stabilizing a textile fabric. A stabilizing fiber layer and an inter-bonding adhesive layer are placed adjacent a back face of a textile fabric. The stabilizing fiber layer contains a plurality of dimensionally stable fibers having a low coefficient of thermal expansion, a low coefficient of moisture expansion or a low coefficient of thermal expansion and a low coefficient of moisture expansion. In one embodiment, the inter-bonding adhesive is a liquid adhesive that is applied and cured after embedding the dimensionally stable fibers into the back face of the textile fabric.

Heat, pressure or heat and pressure are used to embed the dimensionally stable fibers and the inter-bonding adhesive into the textile fabric and to form a stabilized layer in the textile fabric. In one embodiment, the textile fabric is a tufted fabric having a primary backing between face loops and back-laps, and heat, pressure or heat and pressure are used to embed the dimensionally stable fibers and to melt the inter-bonding adhesive into the back-laps from the back face. In one embodiment, heat, pressure or heat and pressure are used to embed the low-melt adhesive through the back-laps and at least partially into the primary backing.

In one embodiment, the inter-bonding adhesive is a liquid adhesive, and the inter-bonding adhesive is applied to the back face of the tufted fabric after the stabilizing fibers have been intermeshed with the back-laps. In one embodiment, a second low-melt adhesive layer is attached to the stabilized layer of the textile fabric. In one embodiment, the textile fabric is a needle-punched felt. In one embodiment, the stabilizing fiber layer is a staple web, a warp of yarns, a warp of filaments, or a fabric or scrim containing glass or aramid fibers. In one embodiment, the stabilizing fiber layer is a blend of low-melt adhesive fibers and dimensionally stable fibers. In one embodiment, a plurality of discrete applications of heat, pressure, or heat and pressure are used to embed the dimensionally stable fibers and inter-bonding adhesive into the textile fabric.

In one embodiment, the stabilizing fiber layer or the inter-bonding adhesive layer is contacted with a heated plate having a pattern of projections, and the projections are pressed toward the back face to embed the dimensionally stable fibers and the inter-bonding adhesive into the textile fabric. In one embodiment, the stabilizing fiber layer or the inter-bonding adhesive layer is contacted with a heated roller plate containing a pattern of projections, and the heated roller is rolled over the stabilizing fiber layer or inter-bonding adhesive layer to press the projections toward the back face to embed the dimensionally stable fibers and the inter-bonding adhesive into the textile fabric. In one embodiment, a plurality of discrete applications of heat, pressure or heat and pressure is used. In one embodiment, a separate pattern of projections is used for each application of heat, pressure or heat and pressure.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate a plurality of embodiments and, together with the following descriptions, explain these embodiments.

FIG. 1 is a schematic representation of an embodiment of a composite containing a textile fabric with an integrated stabilized layer;

FIG. 2 is a schematic representation of an arrangement of a tufted fabric, a low-melt adhesive layer and a stabilizing fiber layer placed over a patterning tool containing a fine and deep surface pattern;

FIG. 3 is schematic representation of the tufted fabric, low-melt adhesive layer and stabilizing fiber layer of FIG. 2 after heated embossing with the patterning tool with the stabilizing fibers intermeshed with the back-laps and the individual fibers within the yarns forming the back-laps;

FIG. 4 is a schematic representation of an arrangement of a tufted cut pile fabric, a low-melt adhesive layer and a stabilizing fiber layer;

FIG. 5 is a schematic representation of another arrangement of a cut pile fabric, a low-melt adhesive layer and a stabilizing fiber layer;

FIG. 6 is a schematic representation of an embodiment of a tufted fabric containing the stabilized layer and an optional thermoplastic layer attached to the bottom of the tufted fabric;

FIG. 7 is a schematic representation of an arrangement of a bulky needle-punched fabric, a low-melt adhesive layer and a stabilizing fiber layer placed over a patterning tool containing cupped needles;

FIG. 8 is a schematic representation of the arrangement of FIG. 7 after the stabilizing fibers are embedded into the needle-punched fabric; and

FIG. 9 is a schematic representation of an embodiment of a needle-punched fabric containing embedded stabilizing fibers and an optional thermoplastic layer attached to the bottom of the needle-punched fabric.

DETAILED DESCRIPTION

The following description of the embodiments refers to the accompanying figures. The same reference numbers in different figures identify the same or similar elements. Reference throughout the whole specification to “one embodiment” or “an embodiment” means that a particular feature, structure or characteristic described in connection with an embodiment is included in at least one embodiment of the subject matter disclosed. Thus, the appearance of the phrases “in one embodiment” or “in an embodiment” in various places throughout the specification is not necessarily referring to the same embodiment. Further, particular features, structures or characteristics may be combined in any suitable manner in one or more embodiments.

Exemplary embodiments are directed to stabilized textile fabrics containing integrated and embedded stabilizing fibers, to floorcoverings containing the stabilized textile fabrics, and to methods for making the stabilized textile fabrics and the floorcoverings containing the stabilizing fibers. The resulting textile fabrics and floorcoverings are stabilized against warping, curling and inter-tile gap formation that can occur due to dimensional instability caused by changes in temperature and moisture. The integrated stabilized layers include a plurality of dimensionally stable fibers or filaments embedded among the fibers of the textile fabric. Dimensionally stable fibers are fibers or filaments having a low coefficient of thermal expansion, a low coefficient of moisture expansion or a low coefficient of thermal expansion and a low coefficient of moisture expansion. Therefore, exposure to changes in temperature or moisture, e.g., humidity, will not result in appreciable dimensional changes in any dimension of the stable fibers. Embedding the dimensionally stable fibers within the dimensionally unstable fibers and filaments of the textile fabric counters the dimensional instability

Referring initially to FIG. 1, exemplary embodiments are directed to a textile composite 300 containing a textile fabric 301. Suitable textile composites include, but are not limited to, floor coverings and flooring tiles. While illustrated as part of a textile composite, exemplary embodiments are directed to the textile fabric itself without any of the additional layers found in the composite. Suitable textile fabrics include woven fabrics, stitch-bonded fabrics, needle-punched fabrics, needle-punched felts, looped tufted fabrics and cut-pile tufted fabrics.

The textile fabric includes a top face 309 and a back face 308 opposite the top face. The top face is spaced from the top face by a thickness 301 of the textile fabric. Before the textile fabric is stabilized, the thickness is the original thickness of the textile fabric. The textile fabric includes a plurality of textile fibers disposed between the top face and the bottom face. Suitable textile fibers include yarns, filaments, and staple fibers.

A stabilized layer 305 extends into the textile fabric from the bottom face. The stabilized layer extends through the bottom 308 into the fabric by a given distance 307 from the back face. The given distance 307 is dependent upon the structure of the floorcovering. Preferably, the given distance is limited to the lower strata to avoid interfering with the fibrous cushion or softness of the textile front. The stabilizing fiber layer includes a plurality of inserted dimensionally stable fibers 306, which are intermeshed or interspersed with the portion of the textile fibers contained in the portion of the textile fabric into which the stabilized layer extends. The weight of the stabilizing fibers sufficient for stabilization is relatively low. In one embodiment, the weight of stabilizing fibers is less than 100 gm/m². Each dimensionally stable fiber maintains dimensional stability upon exposure to changes in moisture, changes in temperature or changes in moisture and temperature because, as compared to the remainder of the structure, each dimensionally stable fiber has a substantially lower low coefficient of thermal expansion, usually lower by an order of magnitude, as well as a much lower tendency to be affected by humidity. Suitable dimensionally stable fibers include, but are not limited to, glass fibers, aramid fibers, carbon fibers and combinations thereof.

The stabilized bottom layer also includes an inter-bonding adhesive interspersed with the original textile fibers and the dimensionally stable fibers. Suitable inter-bonding adhesives include polymeric low-melt adhesives include any adhesive having a melting point below the melting point of the yarns, e.g., the tufted yarns in a tufted fabric, and any additional layers in the textile fabric, e.g., the primary backing layer of the tufted fabric. The low-melt adhesive layer can start as a film or a low melt fabric. In one embodiment, the low melt adhesive layer is a layer of powder, a layer of particles, or a layer of staple fibers. In one embodiment, the low-melt adhesive has a very high melt index. In one embodiment, adhesive is introduced into the back-layer containing the stabilized fiber as a solution or suspension and activated after embedding the stabilizing fibers. In one embodiment, the adhesive is in the form of a latex suspension. In one embodiment, the stabilizing fibers are inserted into a fabric that has already been treated with a latex binder, followed by a second application of binder. In one embodiment, the inter-bonding adhesive is a liquid adhesive that is applied and cured.

In one embodiment, the stabilized textile fabric is part of a textile composite or textile flooring covering that also contains one or more additional layers in contact with and extending from the back face 308. Suitable additional layers include, but are not limited to, additional thermoplastic resin layers 302, e.g., low melt-adhesive layers, fluid barrier layers 303 and cushioning layers 304. The additional layers can be attached in any desired order. Suitable cushioning layers, including felts and foam layers, and fluid barriers, including films, dense fabrics, and cast membranes, are known and available in the art.

Exemplary embodiments are also directed to a method for stabilizing a textile fabric. A textile fabric to be stabilized is selected, and at least one of a layer containing stabilizing fibers, i.e., a stabilizing fiber layer, and an inter-bonding adhesive layer are placed adjacent the back face of the textile fabric. In one embodiment, the inter-bonding adhesive is placed between the back face and the stabilizing fiber layer containing stabilizing fibers. Alternatively, the stabilizing fiber layer containing the stabilizing fibers is placed between the back face and the inter-bonding adhesive. Suitable textile fabrics and inter-bonding adhesives are discussed herein. The stabilized layer contains the plurality of dimensionally stable fibers having a low coefficient of thermal expansion, a low coefficient of moisture expansion or both a low coefficient of thermal expansion and a low coefficient of moisture expansion. Suitable stabilizing fiber layers include, but are not limited to, staple webs, woven or nonwoven fabrics, warps of yarns, warps of filaments and blends of low-melt adhesive fibers and stabilizing fibers, such as glass or aramid fibers.

Heat, pressure or heat and pressure are applied to the combined textile fabric, the stabilizing fiber layer and the inter-bonding adhesive layer to embed the dimensionally stable fibers and the inter-bonding adhesive into the textile fabric. This forms the stabilized layer in the textile fabric. In one embodiment, a single application of heat, pressure or heat and pressure are used to embed the dimensionally stable fibers and the inter-bonding adhesive into the textile fabric. Alternatively, a plurality of discrete applications of heat, pressure, or heat and pressure is used to embed the dimensionally stable fibers into the textile fabric. Embedding of the dimensionally stable fibers is followed by the introduction of liquid adhesive and the setting or curing of the liquid adhesive. In one embodiment, each application is an identical application of heat, pressure or heat and pressure. Alternatively, the amount of heat and the amount of pressure are varied among the plurality of applications.

In addition, the application can be varied with regard to whether heat, pressure or heat and pressure are applied in a given application. For example, heat is applied in a first application followed by pressure before cooling. In one embodiment, multiple applications are used to embed the stabilizing fiber layer and the adhesive layer separately. For example, the inter-bonding adhesive is placed adjacent the bottom face of the textile fabric. Heat, pressure or heat and pressure are applied to embed the inter-bonding adhesive into the textile fabric. Then, the stabilizing fiber layer is placed adjacent the bottom face, and a second application of heat, pressure or heat and pressure is used to embed the stabilizing fiber layer containing stabilizing fibers into the inter-bonding adhesive and textile fabric. In one embodiment, after the inter-bonding adhesive layer and the stabilizing fiber layer containing stabilizing fibers are embedded into the textile fabric to form the stabilized layer within the textile fabric, a second adhesive layer is applied to the stabilized surface layer containing the embedded stabilizing fibers of the textile fabric.

For a tufted fabric having a primary backing between face loops and back-laps, heat, pressure or heat and pressure are used to embed the dimensionally stable fibers and the inter-bonding adhesive into the back-laps from the back face. In one embodiment, a sufficient amount of heat, pressure or heat and pressure is applied to the textile fabric to embed the inter-bonding adhesive through and into the back-laps and partially into the primary backing. Suitable methods for applying heat include using radiant heat, using hot air and using a heated contact surface. Suitable heated contact surfaces include plates or rollers containing a three-dimensional pattern. The three-dimensional patterns include a plurality of protrusions, projections or raised areas. In one embodiment, a plurality of needles, for example, cupped needles, extend from the plate or roller by a given distance. In one embodiment, this given distance corresponds to the distance that the dimensionally stable fibers and inter-bonding adhesive are embedded into the textile fabric.

In one embodiment, a heated plate containing a pattern of projections is pressed against the stabilizing fiber layer containing the dimensionally stable fibers or against the inter-bonding adhesive layer adjacent the back face of the textile. The heated plate is pressed towards the back face, which presses the projections into the textile from the back face to embed the dimensionally stable fibers and the inter-bonding adhesive into the textile fabric. Alternatively, a heated roller with a pattern of projections on its periphery is pressed against the stabilizing fiber layer containing the stabilizing fibers or inter-bonding adhesive layer adjacent the back face of the textile to embed the dimensionally stable fibers and the inter-bonding adhesive into the textile fabric. In one embodiment, the heated roller or heated plate is in a single application to embed the dimensionally stable fibers and the inter-bonding adhesive into the textile fabric. Alternatively, a plurality of discrete applications of the heated plate or heated roller is used. The plurality of discrete applications includes applying the same heated plate or heated roller for each application and using a separate pattern of projections for each application of heat, pressure or heat and pressure or using both flat plates and rollers in combination with plates and rollers containing patterns of projections.

Exemplary embodiments are directed to a tufted fabric containing the integrated layer of stabilizing fibers and to the method for integrating the stabilizing layer into the tufted fabric. In one embodiment, stabilization is achieved after the formation of the tufted fabric. Referring now to FIG. 2, a tufted fabric 100 having a primary backing 104 between the top face 130 and the back face 132 is illustrated. The textile fibers in the tufted fabric are the yarns 101 tufted into the primary backing at a plurality of yarn insertion points 134. The yarns are tufted into the primary backing at a yarn insertion point frequency between adjacent yarn insertion points. The tufted yarns define face loops 102 extending from a first side 136 of the primary backing to the top face 130 and back-laps 103 extending from a second side 138 of the primary backing opposite the first side to the back face 132. The tufted fabric contains relatively tall face loops 102 and relatively shallower back-laps 103. The face loops extend up from the primary backing an original height 111. Any suitable yarns, primary backings and methods for forming a tufted product known and available in the art can be used to form the tufted fabric.

When used in a flooring application, the back-laps are adjacent to the floor and generally flattened. Even though the back-laps are relatively shallower than the face loops, the percentage of tufted yarns within the back-laps that are planarly oriented with respect to the floor is substantial, in particular for highly-patterned tufted flooring constructions. This percentage of planarly oriented yarns in the back-laps frequently exceeds, by weight, the weight of yarns within the face loops, i.e., the pile over the primary backing. Independent expansion and contraction of the yarns and filaments in the flattened back-lap layer is a contributing factor to the effects of thermal and moisture instability of tufted floor coverings. The most commonly used tufting yarns are polyamides, which have a high coefficient of thermal expansion and susceptibility to expansion and contraction with moisture. The use of polyamides increases the effects of back-lap expansion and contraction. Polyolefin yarns are also frequently used as tufted yarns. While polyolefin yarns are not affected by moisture, these yarns have a particularly high coefficient of thermal expansion.

Expansion and contraction of the flattened back-lap layer is reduced through integration of the stabilizing fibers into the backlaps of the tufted fabric. In one embodiment, to integrate the stabilizing layer into the tufted fabric, a inter-bonding adhesive layer 105 and a textile layer 106 containing a plurality of dimensionally stable fibers are placed adjacent the back-laps. As illustrated, the inter-bonding adhesive layer is placed between the stabilizing fiber layer and the back-laps. Alternatively, the stabilizing fiber layer is placed between the inter-bonding adhesive layer and the back laps.

Suitable inter-bonding adhesive layers are disclosed herein and include adhesive layers having a melting point below the melting point of the yarns and backing layer of the tufted fabric. These low-melt adhesive layers can be a loose web of low-melt fibers, a film or a low melt fabric. In one embodiment, the inter-bonding adhesive layer is a layer of powder, a layer of particles, or a layer of staple fibers. In one embodiment, the low-melting fibers, fibrils, or particles are chosen to have a very high melt index to enable them to melt and proceed into the back-laps along with the reinforcing fibers. In one embodiment, the melted fibers, fibrils or particles also enter the primary backing.

Suitable stabilizing fiber layers containing stabilizing fibers include nonwovens, for example, a layer of wet-laid fiberglass fibers. The fiberglass fibers in the stabilizing fiber layer can be bound together using low-melt resin. Alternately, a low melt layer is absent, and following the insertion of the stabilizing fibers into the backlaps, adhesive is applied in a liquid or powder form and melted or cured with heat or heat and pressure. Alternately, the stabilizing fibers in the stabilizing fiber layer are in the form of a woven scrim, a warp of yarns or a weft of yarns, disentagled and broken into shorter lengths and intermeshed with the back-laps. In one embodiment, the inserted stabilizing fiber layer of stabilizing fibers includes low-melting fibers; therefore, a single layer of combined low-melt adhesive and dimensionally stable fibers is pushed and inserted into the back-laps. In one embodiment the inserted layer also includes regular fibers such as polyesters serving to carry shorter or finer stabilizing fibers in a web.

A heated tool 107, e.g., a heated embossing tool, is applied against the layer 106 containing stabilizing fibers. Suitable heated tools include, but are not limited to, a heated roller and a heated flat plate. In one embodiment, the heated tool includes a plurality of projections 108 extending out from a contact face 116 a projection height 110. The plurality of projections is arranged in a pattern of projections and are spaced from each other along the heated tool by a projection spacing 109. The projection height and the projection spacing are selected to enable the heated tool to melt the inter-bonding adhesive layer and intermesh the melted adhesive, back-laps and dimensionally stable fibers without damaging the primary backing. In one preferred embodiment, projections are spaced with a planar frequency to create in the tufted fabric a pattern or insertion points having an insertion point frequency that exceeds the yarn insertion point frequency of tufted yarn insertions into the primary backing. In one embodiment, the projection frequency is at least 50% higher than the loop insertion frequency into the primary backing.

The heated tool is maintained at a temperature above the melting point of inter-bonding adhesive layer 105 and under the melting point of the yarns and filaments in the back-laps 103 and the melting point of the primary backing 104. To intermesh the melted adhesive, back-laps and dimensionally stable fibers, the heated tool is pressed against the stabilizing fiber layer in the direction of arrow A. In one embodiment, an opposing plate (not shown) is also applied to the top face 130 of the face loops 102 to achieve the desired application pressure of the heated tool. In one embodiment, the opposing plate is cooled to avoid softening and crushing the pile of the face loops. In one embodiment, the movement of the heated tool breaks the relatively brittle continuous filaments or longer fibers present in the inserted layer into smaller filaments and fibers to enable the insertion and embedding of the dimensionally stable fibers into the back-laps.

The heated tool is held at the desired application pressure against the stabilizing fiber layer, inter-bonding adhesive layer and back-laps for a dwell time. The dwell time under pressure, and the extent or depth of motion of the heated tool are adjusted to achieve full melting of the inter-bonding layer and propagation of the melted resin into and around the yarns and between filaments of the back-laps and the dimensionally stable fibers. In one embodiment, the dwell time under pressure and the extent or depth of motion of the heated tool are adjusted to achieve propagation of the melted resin partially or slightly into the primary backing.

Application of the heated tool, i.e., calendering, and the associated insertion of adhesive and dimensionally stable particles can be performed in one or more steps. In one embodiment, the heated tool is repeatedly applied to the tufted fabric, for example, randomly as in a needle-punching process, using a stroke of limited depth. In one embodiment, the bottom or back-laps are preheated with radiation, and a cold, i.e., unheated, tool is applied to the back-laps. In one embodiment, the heated tool is a heated roller, and hot roll embossing is performed using multiple passes of the tufted fabric between a heated roller and a cooled roller. In one embodiment, the tufted fabric passes over the heated roller and under an unheated or cooled roller placed against the pile side. Each pass uses either the same process conditions or different process conditions. These process conditions include set-gap, temperature, stroke and pattern. The process conditions are selected to optimize formation of the stabilized layer. In one embodiment, multiple heated tools or heated rollers, or a combination of heated tools and heated rollers are used during multiple discrete applications of heat, pressure or heat and pressure.

In one embodiment, the tufted fabric is cooled or allowed to cool. Preferably the tufted fabric is placed in a flat configuration and cooled. Referring to FIG. 3, the intermeshed melted adhesive, back-laps and dimensionally stable fibers produce the stabilized layer 115 in the tufted fabric. In one embodiment, the stabilized layer is located under the primary backing and includes the back-lap yarns and the dimensionally stable fibers dispersed and embedded among the back-lap yarns and the yarn filaments. In one embodiment, the stabilized layer includes the inter-bonding adhesive interspersed around the back-lap yarns, filaments and dimensionally stable fibers. In one embodiment, the stabilized layer extends from the back face through the back-laps to the primary backing, and the dimensionally stable fibers are intermeshed with the back-laps in accordance with a pattern of insertion points having an insertion point frequency across the back face that exceeds a yarn insertion point frequency across the primary backing. In one embodiment, the stabilizing layer includes the inter-bonding adhesive, and the inter-bonding adhesive extends from the back face through the back-laps and at least partially through the primary backing from the second side.

Heat reaching the bottom of the primary backing does not exceed the melting point of the primary backing. Cushioning offered by the pile is only marginally affected, with the ratio of the final height 112 (FIG. 3) of the face loops to the original height 111 (FIG. 2) being greater than or equal to 0.75, preferably greater than or equal to 0.90.

Referring now to FIG. 4, in one embodiment, the textile fabric is a cut pile fabric 400. The cut pile includes yarns 410 that are inserted or tufted through the primary backing 404 to create the face loops 402 that are cut during the tufting process and the back laps 403 as in the tufted loop fabric. In one embodiment, the inter-bonding adhesive layer 405 is placed below the stabilizing fiber layer 406 containing the stabilizing fibers, which is placed against the back face 432 of the cut pile fabric as illustrated. Heat, pressure or heat and pressure are then applied as described herein.

Referring to FIG. 5, in one embodiment, the cut pile includes yarns 410 that are inserted or tufted through the primary backing 404 to create the face loops 402 and the back laps 403. An adhesive layer 418 is initially applied to the back-laps at the back face 432 of the cut file fabric, i.e., the back-laps are pre-coated with adhesive or pre-embedded with adhesive. The adhesive layer may also be coated onto the back laps as a liquid adhesive. Alternatively, the inter-bonding adhesive layer is placed against the back face, and heat, pressure or heat and pressure are used to embed the back-laps in the low melt adhesive. The stabilizing fiber layer containing stabilizing fibers is placed against the back-laps and the inter-bonding adhesive layer. Heat, pressure or heat and pressure are then applied to form the stabilized bottom layer.

Referring now to FIG. 6, the textile fabric is a tufted fabric 500 having the loops 502 and back laps 503, and the stabilized layer 515 has been created in the back-laps 503. An additional adhesive layer 520 is applied to or attached to the integrated stabilized layer 515. This additional adhesive layer secures or further stabilizes the bottom surface 522 of the stabilized layer, increases cushion and friction between the floor and the bottom surface, and prevents the release of broken or loosened dimensionally stable fibers as the floorcovering containing the tufted fabric is subjected to repeated local intermitted pressure during use.

Referring now to FIG. 7, the textile fabric is a needle-punched fabric 200. The needle punched fabric is formed as a relatively thick and bulky layer having an original height or thickness 210 and containing a plurality of fibers 205. Suitable materials and methods for making needle-punched fabrics are known and available in the art. A inter-bonding adhesive layer 201 is brought into contact with a bottom surface 207 of the needle punched fabric, and a stabilizing fiber layer 202 containing stabilizing fibers is placed into contact with the inter-bonding adhesive layer such that the inter-bonding adhesive layer is disposed between the stabilizing fiber layer 202 and the needle punched fabric. Suitable inter-bonding adhesive layers and stabilizing fiber layers containing stabilizing fibers are disclosed herein.

A heated tool 203, e.g., a heated roller or a heated plate, is moved into contact with the stabilizing fiber layer in the direction of arrow B. The heated tool includes the plurality of projections 204 arranged in accordance with the pattern of projections and insertion points and the desired insertion point frequency. In one embodiment, the projections in the plurality of projections are cupped needles. In one embodiment, the cupped needles extend out from the heated tool a height 216 corresponding to a desired depth of insertion of the inter-bonding adhesive and dimensionally stable fibers into the needle-punched fabric. The heated tool and cupped needles turn the inter-bonding adhesive layer into molten adhesive resin, and the cupped needles drive the dimensionally stable fibers and molten resin into the bottom surface of the needle-punched fabric.

The heated tool is pressed against the stabilizing fiber layer and the back surface in the direction of arrow B to achieve a desired depth of insertion of the cupped needles into the needle-punched fabric. The heated tool is held against the stabilizing fiber layer at the desired depth of insertion of the cupped needles for a length of time sufficient to produce molten inter-bonding adhesive and to drive the molten inter-bonding adhesive into the needle-punched fabric. The heated tool is removed, and the needle-punched fabric is cooled. Referring to FIG. 8, the resulting stabilized needle-punched fabric includes the integrated stabilized layer 215. The final overall height 211 of the stabilized needle-punched fabric including the stabilizing layer is equal to at least 75% of the original height 210 (FIG. 7) of the needle-punched fabric. The stabilized needle punched fabric of FIG. 8 can also be produced by omitting the inter-bonding adhesive layer 201, and after inserting the stabilizing fibers, adding liquid adhesive to the back of the fabric.

Referring now to FIG. 9, in one embodiment, an additional low-melt adhesive layer 214 is applied to or attached to the integrated stabilizing layer 215 of the needle-punched fabric 200. This additional low-melt adhesive layer secures or stabilizes the bottom surface 212, increases cushion and friction between the floor and the bottom surface, and prevents the release of broken or loosened dimensionally stable fibers and yarn filaments as the floorcovering is subjected to repeated local intermitted pressure during use.

The foregoing written description uses examples of the subject matter disclosed to enable any person skilled in the art to practice the same, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the subject matter is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims. 

What is claimed is:
 1. A textile fabric comprising: a top face; a back face spaced from the top face by a thickness; a plurality of textile fibers located within the textile fabric between the top face and the back face; and a stabilized layer extending into the textile fabric and partially along the thickness from the back face, the stabilized layer comprising a plurality of dimensionally stable fibers intermeshed with a portion of the textile fibers and an inter-bonding adhesive; wherein each dimensionally stable fiber maintains dimensional stability upon exposure to changes in moisture, changes in temperate or changes in moisture and temperature.
 2. The textile fabric of claim 1, wherein the inter-bonding adhesive comprises a low-melt adhesive comprising an adhesive melting point lower than a textile fiber melting point.
 3. The textile fabric of claim 1, wherein the inter-bonding adhesive comprises a liquid adhesive introduced after the dimensionally stable fibers have been inserted into the back face of the fabric and cured.
 4. The textile fabric of claim 1, wherein the dimensionally stable fibers comprise glass or aramid fibers.
 5. The textile fabric of claim 1, wherein the dimensionally stable fibers comprise a low coefficient of thermal expansion.
 6. The textile fabric of claim 1, wherein: the textile fabric comprises a tufted fabric comprising a primary backing between the top face and the back face; the textile fibers comprise yarns tufted into the primary backing at a plurality of yarn insertion points to define face loops extending from a first side of the primary backing to the top face and back-laps extending from a second side of the primary backing opposite the first side to the back face; the stabilized layer extends from the back face through the back-laps to the primary backing; and the dimensionally stable fibers are intermeshed with the back-laps and at least a portion of individual fibers within the back-laps.
 7. The textile fabric of claim 6, wherein the dimensionally stable fibers are intermeshed with backlaps in accordance with a pattern of insertion points comprising an insertion point frequency across the back face that exceeds a yarn insertion point frequency across the primary backing.
 8. The textile fabric of claim 6, wherein the inter-bonding adhesive extends from the back face through the back-laps and at least partially through the primary backing from the second side.
 9. The textile fabric of claim 6, wherein the inter-bonding adhesive is a low-melt adhesive
 10. The textile fabric of claim 1, wherein the textile fabric further comprises an additional layer attached to the bottom face and in contact with the stabilized layer.
 11. The textile fabric of claim 1, wherein the textile fabric comprises a needle-punched fabric.
 12. A method for stabilizing a textile fabric, the method comprising: placing a stabilizing fiber layer and an inter-bonding adhesive layer adjacent a back face of a textile fabric, the stabilizing fiber layer comprising a plurality of dimensionally stable fibers having a low coefficient of thermal expansion, a low coefficient of moisture expansion or a low coefficient of thermal expansion and a low coefficient of moisture expansion; using heat, pressure or heat and pressure to embed the dimensionally stable fibers and the inter-bonding adhesive into the textile fabric and to form a stabilized layer in the textile fabric.
 13. The method of claim 12 wherein: the inter-bonding adhesive comprises a liquid adhesive; and the method further comprises curing the inter-bonding adhesive after embedding the dimensionally stable fibers into the back face of the textile fabric.
 14. The method of claim 12, wherein: the textile fabric is a tufted fabric comprising a primary backing between face loops and back-laps; and using heat, pressure or heat and pressure to embed the dimensionally stable fibers and the inter-bonding adhesive into the textile fabric further comprises using heat, pressure or heat and pressure to embed the dimensionally stable fibers and to melt the inter-bonding adhesive into the back-laps from the back face.
 15. The method of claim 14, wherein using heat, pressure or heat and pressure to embed the dimensionally stable fibers and the inter-bonding adhesive into the textile fabric comprises using heat, pressure or heat and pressure to embed the low-melt adhesive through the back-laps and at least partially into the primary backing.
 16. The method of claim 12, wherein: the inter-bonding adhesive comprises a liquid adhesive; and the method further comprises applying the inter-bonding adhesive to the back face of the tufted fabric after the stabilizing fibers have been intermeshed with the back-laps.
 17. The method of claim 12, wherein the method further comprises attaching a second low-melt adhesive layer to the stabilized layer of the textile fabric.
 18. The method of claim 12, wherein the textile fabric comprises a needle-punched felt.
 19. The method of claim 12, wherein the stabilizing fiber layer comprises a staple web, a warp of yarns, a warp of filaments, or a fabric or scrim containing glass or aramid fibers,
 20. The method of claim 12, wherein the stabilizing fiber layer comprises a blend of low-melt adhesive fibers and dimensionally stable fibers.
 21. The method of claim 12, wherein using heat, pressure or heat and pressure to embed the dimensionally stable fibers and the inter-bonding adhesive into the textile fabric further comprises using a plurality of discrete applications of heat, pressure, or heat and pressure to embed the dimensionally stable fibers and inter-bonding adhesive into the textile fabric.
 22. The method of claim 12, wherein using heat, pressure or heat and pressure to embed the dimensionally stable fibers and the inter-bonding adhesive into the textile fabric and to form a stabilizing layer in the textile fabric further comprises: contacting the stabilizing fiber layer or the inter-bonding adhesive layer with a heated plate comprising a pattern of projections; and pressing the projections toward the back face to embed the dimensionally stable fibers and the inter-bonding adhesive into the textile fabric.
 23. The method of claim 12, wherein using heat, pressure or heat and pressure to embed the dimensionally stable fibers and the inter-bonding adhesive into the textile fabric and to form a stabilizing layer in the textile fabric further comprises: contacting the stabilizing fiber layer or the inter-bonding adhesive layer with a heated roller comprising a pattern of projections; and rolling the heated roller over the stabilizing fiber layer or inter-bonding adhesive layer and pressing the projections toward the back face to embed the dimensionally stable fibers and the inter-bonding adhesive into the textile fabric.
 24. The method of claim 12, wherein using heat, pressure or heat and pressure to embed the dimensionally stable fibers and the inter-bonding adhesive into the textile fabric further comprises using a plurality of discrete applications of heat, pressure or heat and pressure.
 25. The method of claim 12, wherein using the plurality of discrete applications of heat, pressure or heat and pressure further comprises using a separate pattern of projections for each application of heat, pressure or heat and pressure. 